Rather nervous about the changes in battle. Looks like two things going on - they are nerfing HP a little and buffing Def, which is fine, as long as you have it, and they are doing a bit of a stat squish to prepare for raising the level cap.
I just hope that all the pokemon I invested heavily in are still good. I remember just before the first stat change I decided to commit to Lapras to take down Dragonites, got my level 30 Lapras up over CP2500, and then he got nerfed to just under CP2200. Not fun.